I skip getting a Starbuck's latte, and avoid adding extra guac at Chipotle.
I'm kidding, that stuff has no affect on anything.
Justifiable, as in "does this make practical sense", is not the word, because it doesn't. Justifiable, as in, "does it fit within my budget?" yes that's accurate. I don't have a short answer to why my personal budget is that flexible, but I do remember there was a point in my life where I would ask the same thing as you about other people. The reality is that you either have it or you don't. That being said, nothing I had been doing for money is really going to max this kind of machine out or improve my craft. But things that used to be computationally expensive won't be anymore. Large catalogues of 24 megapixel RAWs used to be computationally expensive. Now I won't even notice, even with larger files and larger videos, and can expand what I do there along with video processing, which is all just entertainment. But I can also do that while running a bunch of docker containers and VMs... within VMs, and not think about it.
This machine, for me, is the catalyst for greater consumptive spending though. I've held off on new cameras, new NASs, new local area networking, because my current laptop and devices would chug under larger files.
Hope there was something to glean from that context. But all I can really offer is "make, or simply have, more money", not really profound.